One standard deviation happens one draw out of three, two standard deviations one out of twenty, three standard deviations is one out of one hundred.

落在一个标准偏差之外的概率是1/3,两个标准差之外的概率是1/20,三个标准差之外是百分之一

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And then I could also do a Gaussian one here, with the mean of and the standard deviation of volatility divided by 2.

然后我在这里再写一个高斯分布的函数，它的浮动值的平均值和,标准偏差值都除了2。

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